drummerbart

ok so here's my problem. i have a 98 si coupe power everything. when i go and pull the button up to bring the window up it does so but stops about a half an inch too short, and when i try to pull the button to bring it up some more the window just keeps hopping on the track. i took the door panel apart and couldnt really see what was wrong. i saw the gear that brings up the window and the arms but couldnt really see what was wrong. so please any help here would be greatly appreciated.